From 5c6bd75d06db512515a3781aa97e42df2faf0815 Mon Sep 17 00:00:00 2001 From: Alasdair G Kergon Date: Mon, 26 Jun 2006 00:27:34 -0700 Subject: [PATCH] dm: prevent removal if open If you misuse the device-mapper interface (or there's a bug in your userspace tools) it's possible to end up with 'unlinked' mapped devices that cannot be removed until you reboot (along with uninterruptible processes). This patch prevents you from removing a device that is still open. It introduces dm_lock_for_deletion() which is called when a device is about to be removed to ensure that nothing has it open and nothing further can open it. It uses a private open_count for this which also lets us remove one of the problematic bdget_disk() calls elsewhere. Signed-off-by: Alasdair G Kergon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/md/dm.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers/md/dm.h') diff --git a/drivers/md/dm.h b/drivers/md/dm.h index 71ddd1e2300..9ebb24b037b 100644 --- a/drivers/md/dm.h +++ b/drivers/md/dm.h @@ -123,5 +123,7 @@ void dm_stripe_exit(void); void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size); union map_info *dm_get_mapinfo(struct bio *bio); +int dm_open_count(struct mapped_device *md); +int dm_lock_for_deletion(struct mapped_device *md); #endif -- cgit v1.2.3